/*
An application can use the DeviceIoControl function to perform 
direct input and output operations on, or retrieve information 
about, a floppy disk drive, hard disk drive, tape drive, or CD-ROM drive. 

For a list of standard control codes included in the SDK documentation, 
see the Remarks section of DeviceIoControl.

The following example demonstrates how to retrieve information 
about the first physical drive in the system. 

It uses the CreateFile function to retrieve the device handle to 
the first physical drive, and then uses DeviceIoControl with 
the IOCTL_DISK_GET_DRIVE_GEOMETRY control code to fill 
a DISK_GEOMETRY structure with information about the drive.
*/

//Calling DeviceIOControl Examples



#define UNICODE 1
#define _UNICODE 1

/* The code of interest is in the subroutine GetDriveGeometry. The 
   code in main shows how to interpret the results of the call. */

#include <windows.h>
#include <winioctl.h>
#include <stdio.h>

BOOL GetDriveGeometry(DISK_GEOMETRY *pdg)
{
  HANDLE hDevice;               // handle to the drive to be examined 
  BOOL bResult;                 // results flag
  DWORD junk;                   // discard results

  hDevice = CreateFile(TEXT("\\\\.\\PhysicalDrive0"),  // drive to open
                                      //\\\\.\\PhysicalDrive0
                    0,                // no access to the drive
                    FILE_SHARE_READ | // share mode
                    FILE_SHARE_WRITE, 
                    NULL,             // default security attributes
                    OPEN_EXISTING,    // disposition
                    0,                // file attributes
                    NULL);            // do not copy file attributes

  if (hDevice == INVALID_HANDLE_VALUE) // cannot open the drive
  {
    return (FALSE);
  }

  bResult = DeviceIoControl(hDevice,        // device to be queried
            IOCTL_DISK_GET_DRIVE_GEOMETRY,  // operation to perform
            NULL, 0,                        // no input buffer
            pdg, sizeof(*pdg),              // output buffer
            &junk,                          // # bytes returned
            (LPOVERLAPPED) NULL);           // synchronous I/O

  CloseHandle(hDevice);

  return (bResult);
}

int main(int argc, char *argv[])
{
  DISK_GEOMETRY pdg;            // disk drive geometry structure
  BOOL bResult;                 // generic results flag
  ULONGLONG DiskSize;           // size of the drive, in bytes

  bResult = GetDriveGeometry (&pdg);

  if (bResult) 
  {
    printf("Cylinders = %I64d\n", pdg.Cylinders);
    printf("Tracks/cylinder = %ld\n", (ULONG) pdg.TracksPerCylinder);
    printf("Sectors/track = %ld\n", (ULONG) pdg.SectorsPerTrack);
    printf("Bytes/sector = %ld\n", (ULONG) pdg.BytesPerSector);

    DiskSize = pdg.Cylinders.QuadPart * (ULONG)pdg.TracksPerCylinder *
      (ULONG)pdg.SectorsPerTrack * (ULONG)pdg.BytesPerSector;
    printf("Disk size = %I64d (Bytes) = %I64d (Gb)\n", DiskSize,
           DiskSize / (1024 * 1024 * 1024));
  } 
  else 
  {
    printf ("GetDriveGeometry failed. Error %ld.\n", GetLastError ());
  }

  system("pause");
  return ((int)bResult);
}
